Selected topics on HfO 2 gate dielectrics for future ULSI CMOS devices

Abstract

Based on our recent investigation on HfO 2 high-k gate dielectrics, we review the Hf based gate dielectric in the future ULSI CMOS devices in the following aspects: How long HfO 2 can be used satisfactorily, assessed from the gate tunneling and scalability; how thin EOT can be grown technologically, assessed by interfacial layer thickness; and how high operating voltage can be employed for 10 years reliable operation, assessed by charge trapping and threshold voltage shift. © 2004 IEEE.